1. Field of the Invention
The present invention relates generally to building construction and more particularly, to device for adjoining overlapping segments of interconnecting reinforcement bars.
2. Description of the Prior Art
Conventional commercial buildings are predominantly masonry construction. Foundations of commercial buildings are typically reinforced with reinforcement bar, commonly referred to as rebar, and walls of such buildings are generally constructed of block having cells filled with grouting and reinforced with reinforcement bar.
Construction of commercial buildings generally begins with the formation of footings which support walls. The footings vertically support a series of spaced apart reinforcement bar in a upright position. In accordance with known methods of construction, each reinforcement bar typically extends five feet or more above the footings, as is shown in prior art FIG. 1. The block walls are constructed with the reinforcement bar contained within. In accordance with known methods of construction, blocks have to be raised above the reinforcement bar and lowered to footing with the reinforcement bar extending through a hollow block cell. A series of blocks are laid upon one another following the same method of raising the blocks above the reinforcement bar and lowering the blocks to a subsequent course of blocks with the reinforcement bar extending through various block cells. The blocks are joined to the footings and other blocks with grouting. Once a numbered of layers of block have been laid, and while a desired length of each spaced apart reinforcement bar remains exposed beyond the block wall being formed, another length of reinforcement bar is tied to each the exposed portion of each spaced apart reinforcement bar. This method is continued until a wall of desired height is achieved. Once a wall of desired height is achieved, the block cells are filled with grouting, forming a cement masonry unit (CMU).
Depending on factors, such as the structural dimensions of the commercial building and building codes, a certain amount of reinforcement bar overlap is required. Overlap may be in the order of sixteen inches or more. In accordance with the present methods, this length of overlap is measured manually and the two segments of reinforcement bar are manually tied together with tie wire. This method is inefficient with regard to the man hours required for tying the overlapping segments together, wasteful due to excessive overlap, and lends itself to error should insufficient overlap occur.
In forming a typical foundation, layers of sand, stone and plastic are provided, and a grid of reinforcement bar is formed upon these layers. This grid is formed by overlapping segments of reinforcement bar tied together in a manner similar to that set forth above. A first layer of reinforcement bar is arranged spaced apart relative to one another. A second layer of reinforcement bar is arrange spaced apart relative to another and perpendicular to the first layer to form a grid of reinforcement bar. The two layers of reinforcement bar are tied to one another, thus fixing the two layers relative to one another.
Coupling devices for adjoining reinforcement bars are known in the prior art. For example, U.S. Pat. No. 3,390,905, issued Jul. 2, 1968, to Donald A. Stewart, discloses holding and locating devices for overlapping structural members comprising two separately formed elements partly embrace overlapping portions of the two structural members. The elements are secured together by one or more separately formed tie members. The structural members are freely slidable in the elements. U.S. Pat. No. 4,692,052, issued Sep. 8, 1987, to Alfred A. Yee, discloses a splice sleeve for connecting overlapping reinforcement bars. The sleeve includes a rigid tubular sleeve for receiving the overlapped ends of the reinforcement bars. The tubular sleeve is filled with a hardenable material to resist axial tension exerted on the reinforcement bars. U.S. Pat. No. 5,365,715, issued Nov. 22, 1994, to James W. Steinmetz et al., discloses a rod tying a including an attachment element and a mating centering element. In use, the attachment element is attached to one of the members to be tied and the centering element is used to align and juxtapose the attachment element to a stationary member. Two coils of wire are wrapped around the attachment element and the centering element. Upon separation of the attachment element and the centering element, the coils of wire are adapted to tighten around the aligned members and tie the members together.
None of the above inventions, taken either singly or in combination with other inventions, is seen to describe the instant invention as claimed.